This Core will provide essential technical facilities for microscopic and imaging studies of muscle and other tissues. This Core has a history of 30 years of being a part of a previous PPG funded in this division. We have always taken the stance that structure should be correlated with function. Dr. Odile Mathieu-Costello, who has recently retired, ran this core for a number of years with a strong emphasis on morphometry, especially in peripheral tissue. With the emphasis in this current application on cell imaging, cell biochemistry, and muscle morphometry, we plan to continue the outstanding work that our Division has had in this area. Dr. Hogan will now direct this Core, and he brings unique expertise to this highly specialized area. We feel that with the work Dr. Hogan has done and continues to conduct using imaging, biochemical, and morphological techniques, he is the ideal person to continue to head the scientific aspects of this Core. We see the Tissue Imaging, Biochemistry, and Morphology Core as an essential feature of the Program Project. The Core will partially support the salaries of Dr. K. Tang and an SRA, H. Wagner. Dr. Tang has extensive experience with immunohistochemistry, tissue morphology, and transgenic techniques. The SRA has intensive experience in the preparation of sections of muscle and other tissues for light and electron microscopy, and histochemistry. She will work primarily in the preparation of tissues for both light and electron microscopy. She understands the needs of our group well, and is well trained in the execution of tissue preparation and imaging. Morphometric analysis requires a large number of sections and fields to be examined, and tissue sectioning, especially for electron microscopy, is extremely time consuming. Based on the output of the Core in the past cycles and the studies proposed in this application, a half-time technician is clearly needed to meet the needs of the different projects.